The Drag and Drop Firmware Update USB Secure Bootloader for the Atmel SAM Embedded Microcontrollers was initially written for Planet 1's products, but proved to be so useful it has become a product in it's own right.

Features

• No end-user firmware update tools required (hardware or software)
• Your product appears as a USB drive for 30s when the CPU is reset (but not power-on)
• Drag and drop firmware on to USB drive to update (works with PC and Mac)
• 256-bit AES encryption
• Prevents update of incorrect product firmware
• Powers-on immediately in to your application
• Simple integration in to your build process
• Pre-built firmware bootloader and PC tool supplied - ready to go
• Your firmware is CRC checked by the bootloader before it is executed
• Automatic flash page locking and read protection when your application is executed
  
• Only 20K of flash used
• Inexpensive, per product royality free licence

End User Usage

1. Download new (encrypted) firmware from your web-site or an email distribution
2. Plug the USB cable in to your product and a PC (or MAC)
3. Press the reset button, a new USB Drive will appear on the PC (called "FIRMWARE UP")
4. Within 30 seconds, drag and drop the firmware file on to the "FIRMWARE UP" drive
5. The drive will disappear and re-appear as few seconds later
6. Within 30s open the drive and double click on "status.txt" to confirm the firmware was updated successfully (incorrect firmware will be rejected, leaving the current firmware intact)
7. Power cycle (or wait for the 30s to end) and the new firmware will run 

Developer Usage

1. Purchase the Bootloader and PC Build tool from Planet 1 Ltd for your product. This is a product based licence with unlimited Bootloader copies for that product, you will have a new (unique) key pre-compiled in the Bootloader and PC tool for each product license you purchase.

2. Within Atmel Studio:

   1. Add the PC tool as a Post Build event command-line (detailed instruction included)
   2. Change the .text section start address in the Linker Memory Settings (detailed instruction included)
   3. Rebuild the project
   4. Along with your <project>.bin file a <project>.fw file will be generated each time you build

Manufacture and Test

1. Program the Bootloader (and read-protect the flash if you wish) using your preferred tools
2. Test the USB and Firmware update process by following the End User Usage instruction above (the flash will be locked and read-protected by the bootloader)
3. Test functionality

Alternatively:

1. Generate a single combined Bootloader and application image by reading flash within the 30s (after the first firmware drag and drop), use this single firmware image for faster manufacture programming times.This is made possible because the Bootloader locks and read-protects the flash just before the application executes, thus allowing the developer to read the whole flash as a single image (during the first drag and drop 30s only).
2. Test functionality